Skin cooling, solution modification among factors shown to minimize pain of anesthetic injection

The authors comprehensively summarize existing evidence for methods used to reduce injection pain, specifically in the context of periocular procedures.

Study design

This meta-analysis reviewed studies from 1946 through 2018 for papers pertaining to reducing pain with periocular surgery. The analysis spans 23 articles, including 1,135 patients. The methods to reduce pain included adjusting the type of local anesthetic, solution pH, solution temperature, distraction method and injection technique.

Outcomes

Various factors can help minimize pain with periorbital local anesthetic injections. Decreasing pain can improve the patient experience for local procedures. The best methods to reduce pain include: modifying the solution (buffering, dilution, warming), distraction with vibration, cooling the skin with ice, transconjunctival topical anesthetic and decreasing the rate of injection.

Limitations

Limitations include the heterogenous mix of studies and the exclusion publications that were not in the English language (although these were included if the abstract was in English). The meta-analysis only allows for an indirect comparison of the various techniques to reduce pain.

Clinical significance

Periocular surgery is often performed under local anesthesia. The injection of a local anesthetic is painful and anxiety provoking for many patients. Techniques to reduce pain associated with local anesthetic injection can improve the patient experience. There are many readily available techniques to help decrease pain with local anesthetic injection, including buffering of the solution, warming the solution, adjusting the type of local anesthetic, vibration distraction and applying topical anesthetic drops. Future comparisons of techniques to reduce pain with local anesthetic injections could be helpful.